Field of Invention
The present invention relates to a hub, especially relates to a hub having complex power converters for data transmission and rapid charge.
Description of Related Art
In recent years, with the development of science and technology, sizes of various portable devices (such as smart phones) become smaller gradually, and develop for the direction which the portable device is convenient to carry. Certainly, the portable devices usually need to maintain normal operation depending on a battery, and the portable devices are required to charge immediately when the battery power is exhausted.
Currently, a common USB 2.0 port can provide a rated current of 500 mA, a common USB 3.0 port can provide a rated current of 900 mA, and a common USB Type-C port can provide a rated current of up to 1.5 A or 3 A. A mobile electronic device generally detects the type of an USB port by means of various communication methods (for example, DP and DN signals, cc1 and cc2 signals for USB Type-C, or FSK technology of 5 VBUS for USB PD) to determine whether the USB port is general purpose for signal transmission (such as SDP) or an USB port for high charging current only (such as DCP) or both of the two function (such as CDP). The type of the USB port is identified after the mobile electronic device handshakes with an electronic device (for example, a desktop computer) that the USB port belongs to, and after a charging condition (including a voltage level and a charging current level) is determined, quick charging can start (where quick charging is defined as charging current higher than 500 mA). After the quick charging function is enabled, some mobile devices can indicate a charging current of about 1 A, some can indicate a charging current of up to 2.4 A, and mobile devices with an USB Type-C port can even indicate a maximum charging current of 3 A. However, the higher the charging current is, the greater the voltage drop caused by USB cable, connector and the like will be. An extra low output voltage may result in abnormal operation of the electronic device.
Nowadays, the portable devices can be charged via USB port on PC or apply the AC adapter (or named by charger). USB ports on PC or NB usually provide standard charging mode (SDP), 500 mA. However, with the various portable devices, users often own at least two kinds of the portable devices, such as mobile phones, portable HDD, tablets, or digital camera etc., and the amount of USB ports in a general desktop computer may be not enough for use. Therefore, users can buy an USB hub to expand the amount of the USB ports. Especially small size notebook computers emphasize the portability, and may have two USB ports or even one port in future. In addition to carry the devices such as mobile phones, notebook computers, and the hub etc., the peripherals and accessories such as adapters for charging will increase the amount users carried and are very inconvenient to carry when users go out. At present, there are a number of electronic products for charging rapidly (such as car charger, or AC to multi-USB ports charger). Although the products can provide enough power to mobile electronic devices for charging rapidly, but the portable devices are unable to transmit data. In addition, although the traditional USB hub can expand the USB ports for the portable devices to transmit data simultaneously, but the general USB ports just provide limited power for preventing over current or the lack of function to activate quick charging and data transmission simultaneously (such as CDP mode). Thus, the portable devices are allowed to perform a standard charging mode only so that the function of rapid charge can't be provided by the hub. Furthermore, fewer hubs still can supply more power via an additional adapter, but at least two accessories are needed to carry when user go out, and this also increases the cost and inconvenience. Wherein, some USB hubs even need to switch manually between the USB power and the external power converter by a manual switch for either data transmission or charging function only, which is quite inconvenient.
Therefore, how to solve the problems described above, and create a product that integrates the function of data transmission, better portability, rapid charge and low cost, which need to consider by the skilled person.